The little octopus picks up two halves of a coconut shell and carries them across the ocean floor with her suckers. Suddenly, startled, she drops the shell halves and dives inside.

Like a lot of you, I watched that video and wondered, "Just how smart are cephalopods, anyway?"

Turns out, on a scale of one to chimpanzee, octopuses are probably somewhere close to matching wits with a dog. We don't really know for sure. It's difficult to devise intelligence testing for an animal that is so clearly different from us.

That said, research does offer some tantalizing hints that we may need to rethink our anti-invertebrate biases. Octopuses have personalities. They can recognize and respond to individual humans. And there's even some evidence that they play.

The little octopus picks up two halves of a coconut shell and carries them across the ocean floor with her suckers. Suddenly, startled, she drops the shell halves and dives inside.

Like a lot of you, I watched that video and wondered, "Just how smart are cephalopods, anyway?"

Turns out, on a scale of one to chimpanzee, octopuses are probably somewhere close to matching wits with a dog. We don't really know for sure. It's difficult to devise intelligence testing for an animal that is so clearly different from us.

That said, research does offer some tantalizing hints that we may need to rethink our anti-invertebrate biases. Octopuses have personalities. They can recognize and respond to individual humans. And there's even some evidence that they play.